Knapsack with padded back

ABSTRACT

A knapsack with padded back includes a knapsack main body defining at least one receiving space, at least one shoulder strap connected to a back of the knapsack main body, and a pad attached to at least an outer side of the back of the knapsack main body. The pad consists of an inner watertight layer in contact with the back of the main body, a middle air-permeable elastic layer, and an outer cover layer connected along an outer periphery to a boundary of the back of the main body. The middle air-permeable elastic layer is made of a thermoplastic elastic material and formed with a plurality of voids to provide the pad with good cushioning and air convection effects, making the knapsack with padded back more comfortable for carrying.

FIELD OF THE INVENTION

The present invention relates to a knapsack with padded back, and more particularly to a knapsack having a padded back that provides good cushioning and air convection effects and makes the knapsack more comfortable for carrying.

BACKGROUND OF THE INVENTION

A conventional knapsack typically defines a receiving space, and has two shoulder straps connected to a back thereof. The back of the conventional knapsack is usually provided at an outer side with an inner layer of padding material, which may be cotton, sponge, or foamed plastics, and an outer cover layer, which is located at an outer side of the inner padding material layer and connected along an outer periphery to a boundary of the back of the knapsack, and is formed with a plurality of air vents. The inner padding material layer forms a buffer between the knapsack and a user's back, and the outer cover layer with air vents allows discharging of hot air accumulated in the inner padding material layer.

Since the inner padding material layer provided at the back of the conventional knapsack includes only one thin layer of cotton, sponge, or foamed plastics, it tends to be fully compressed and flattened to lose its buffering function when the knapsack is heavily loaded. The fully compressed and flattened padding material layer, including the cotton, the sponge, or the foamed plastics, shall have an overly high density to adversely affect the discharge of hot air accumulated in the padding material layer. With the hot air stored in the padding material layer for a prolonged time, the padded back of the conventional knapsack would cause discomfort to the user's back.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a knapsack having a padded back that provides good cushioning and air convection effects and makes the knapsack more comfortable for carrying, particularly when the knapsack is carried while the user is walking.

To achieve the above and other objects, the knapsack with padded back according to the present invention includes a knapsack main body defining at least one receiving space, at least one shoulder strap connected to a back of the knapsack main body, and a pad attached to at least an outer side of the back of the knapsack main body. The pad consists of an inner watertight layer in contact with the back of the main body, a middle air-permeable elastic layer, and an outer cover layer connected along an outer periphery to a boundary of the back of the main body. The middle air-permeable elastic layer is made of a thermoplastic elastic material and formed with a plurality of voids to provide the pad with good cushioning and air convection effects, making the knapsack with padded back more comfortable for carrying.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

FIG. 1 is an assembled rear perspective view of a knapsack with padded back according to a preferred embodiment of the present invention;

FIG. 2 is a partially exploded view of FIG. 1;

FIG. 3 is a partially sectioned side view of the knapsack of FIG. 1;

FIG. 4 is a side view showing the knapsack of FIG. 1 is carried on a user's back;

FIG. 5 is a partially sectioned side view showing how the padded back of the knapsack of FIG. 1 functions when the knapsack is in use;

FIG. 6 is a rear perspective view of a knapsack with padded back according to another embodiment of the present invention; and

FIG. 6-1 is an enlarged view of the circled area of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 1 and 2 that are assembled and partially exploded rear perspective views, respectively, of a knapsack with padded back according to a preferred embodiment of the present invention, and to FIG. 3 that is a partially sectioned side view of the knapsack of FIG. 1. As shown, the knapsack with padded back according to the preferred embodiment of the present invention includes a main body 1 defining at least one receiving space 11, which is openably closed with a fastening element 12, such as a zipper; at least one shoulder strap 2 connected at two ends to upper and lower ends of a back of the main body 1; and a pad 3 attached to at least an outer side of the back of the main body 1.

The pad 3 consists of an inner watertight layer 31, which is in direct contact with the back of the knapsack main body 1; a middle air-permeable elastic layer 32 located at an outer side of the watertight layer 31 opposite to the back of the knapsack main body 1; and an outer cover layer 33, which is located at an outer side of the middle air-permeable elastic layer 32 and formed with a plurality of holes 331 extended through a full thickness of the outer cover layer 33, and connected along an outer periphery to a boundary of the back of the main body 1 to enclose the inner and the middle layers 31, 32 between the outer cover layer 33 and the back of the main body 1.

The middle air-permeable elastic layer 32 is a three-dimensional structure made of a thermoplastic elastic material 321 and containing a plurality of voids 322. The thermoplastic elastic material 321 may be selected from the group consisting of polyolefin plastics, olefin copolymer/terpolymer plastics, polyvinyl chloride plastics, polyamide plastics, polyurethane plastics, and polyester plastics.

Please refer to FIG. 4 that is a side view showing the knapsack of the present invention is carried on a user's back, and to FIG. 5 that is a partially sectioned side view showing how the pad 3 functions when the knapsack of the present invention is in use. As shown, the pad 3 has an outmost surface in contact with a user's back when the knapsack is carried on the user's back. The outmost surface of the pad 3 may be configured as a planar surface or a curvy surface corresponding to the contour of human body's back. In the illustrated preferred embodiment of the present invention, the knapsack has two shoulder straps 2 and the pad 3 has a curvy outmost surface. To carry the knapsack of the present invention on back, the user first extends two arms through the two shoulder straps, so that the shoulder straps 2 are supported on the user's two shoulders and the outer cover layer 33 of the pad 3 is in contact with the user's back. When the main body 1 of the knapsack is heavily loaded, the middle air-permeable elastic layer 32, which is made of a thermoplastic elastic material 321 and containing a plurality of voids 322, forms an idea cushion to buffer the pressure applied to the user's back by the loaded knapsack main body 1, allowing the user to comfortably carry the knapsack on the back. When the user carries the knapsack while walking, the outer cover layer 33 and the middle air-permeable elastic layer 32 of the pad 3 are constantly compressed or loosened between the user's back and the loaded main body 1 in a natural way. When these two layers 32, 33 are compressed, hot air in the voids 322 of the middle layer 32 is discharged via the through holes 331 of the outer cover layer 33 out of the pad 3 into the air, and when the two layers 32, 33 are loosened, external cool air is sucked into the voids 322 of the middle layer 32 via the through holes 331 of the outer cover layer 33, providing an air convection effect at the pad 3. With the cushioning effect and the air convection effect provided by the pad 3, the user's back is not subjected to heavy load and sweat all the time. On the other hand, the inner watertight layer 31 of the pad 3 prevents the user's sweat from penetrating into the receiving space 11 of the knapsack main body 1, ensuring things held in the main body 1 are always in a dry and good condition.

FIG. 6 shows a knapsack with padded back according to another embodiment of the present invention. In this embodiment, the pad 3 is not only provided at the back of the knapsack main body 1, but also at an inner surface of every shoulder strap 2 that is in contact with the user's shoulder, as can be clearly seen from FIG. 6-1, which is an enlarged view of the circled area of FIG. 6. With the cushioning effect provided by the pad 3 at every shoulder strap 2, the user's shoulders are protected against heavy pressure from the heavily loaded knapsack main body 1.

With the middle air-permeable elastic layer 32, the pad 3 at the back of the main body 1 and/or the inner surface of the shoulder straps 2 of the knapsack provides good cushioning and air convection effects, making the knapsack more comfortable for carrying.

The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

1. A knapsack with padded back, comprising: a knapsack main body defining at least one receiving space therein; at least one shoulder strap being connected at two ends to upper and lower ends of a back of said knapsack main body; and a pad being attached to at least an outer side of said back of said knapsack main body; said pad consisting of an inner watertight layer, which is in direct contact with said back of said knapsack main body, a middle air-permeable elastic layer located at an outer side of said inner watertight layer opposite to said back of said knapsack main body, and an outer cover layer, which is located at an outer side of said middle air-permeable elastic layer and connected along an outer periphery to a boundary of said back of said main body to enclose said inner and said middle layers between said outer cover layer and said back of said main body; and said middle air-permeable elastic layer being a three-dimensional structure made of a thermoplastic elastic material and containing a plurality of voids.
 2. The knapsack with padded back as claimed in claim 1, wherein said pad has an outmost surface configured as a planar surface.
 3. The knapsack with padded back as claimed in claim 1, wherein said pad has an outmost surface configured as a curvy surface corresponding to a contour of human body's back.
 4. The knapsack with padded back as claimed in claim 1, wherein said thermoplastic elastic material comprises polyolefin plastics.
 5. The knapsack with padded back as claimed in claim 1, wherein said thermoplastic elastic material comprises olefin copolymer/terpolymer plastics.
 6. The knapsack with padded back as claimed in claim 1, wherein said thermoplastic elastic material comprises polyvinyl chloride plastics.
 7. The knapsack with padded back as claimed in claim 1, wherein said thermoplastic elastic material comprises polyamide plastics.
 8. The knapsack with padded back as claimed in claim 1, wherein said thermoplastic elastic material comprises polyurethane plastics.
 9. The knapsack with padded back as claimed in claim 1, wherein said thermoplastic elastic material comprises polyester plastics.
 10. The knapsack with padded back as claimed in claim 1, wherein said outer cover layer of said pad is formed with a plurality of holes extended through a full thickness of said outer cover layer.
 11. The knapsack with padded back as claimed in claim 1, wherein said pad is further provided at an inner surface of every said shoulder strap that is in contact with a user's shoulder. 